So, You Were Expecting a Pigeon?; In City Bustle, Herons, Egrets and Ibises Find a Sanctuary

By JOSEPH BERGER

Published: December 4, 2003

Correction Appended

The spot was in the heart of an urban bedlam, surrounded by the hurtling traffic of the Triborough Bridge, the smokestacks of Con Edison, the grim warrens of Rikers Island, the roar of La Guardia jets and three sewage treatment plants.

Yet there hunched on a beach on South Brother Island in the East River, looking like old philosophers mulling a tangled question, were five great blue herons.

These long-legged waterfowl would seem to find the quiet of the Everglades more congenial than the hurly burly of New York City. But for many years now, herons -- as well as egrets, ibises and other wading birds -- have been nesting or roosting on South Brother Island and 13 other uninhabited islands managed by New York City's Parks Department or the National Park Service with help from the New York City Audubon Society.

Several of the islands are unlikely sanctuaries, a stone's throw from Gracie Mansion or the United Nations or Co-op City. Yet the fact that there are wading birds hovering near these landmarks is a lyrical measure of the restored health of the city's waterways and of the salt marshes where the birds feed.

While the herons' taste for New York may suggest a wackiness that should make them fit right in with the city's other eccentrics, ornithologists think the birds' choice may be a sign of shrewd intelligence. A healthy island amid turbulent waters and urban eyesores is actually an ''oasis in the wild,'' said Alexander R. Brash, chief of the Parks Department's natural resources group, discouraging countrified predators like barn owls and raccoons as well as trespassing humans.

While 1,837 pairs of herons, egrets and ibises have been thriving on seven of the 14 islands, the news is not all good. These species have all but abandoned three islands in Staten Island's refinery-lined Kill Van Kull and Arthur Kill waterways, where they once flourished.

Some blame human intruders, pollution and the proliferation of trees unsuitable for nesting. Others say wading birds have forsaken those islands because owls, hawks and raccoons who once fed on garbage in the Fresh Kills landfill have ventured farther afield as the landfill gradually closed and are preying on heron eggs and young on the island.

By contrast, South Brother and its bigger sibling, North Brother Island, have resisted such an invasion. North Brother's vegetation -- a jungle of thick brush, low trees and tangled bittersweet vines set among the ruins of a dozen quarantine and hospital buildings -- has produced a secure haven for the black-crowned night heron, the city's most populous heron species. More than 230 crude nests of sticks and twigs were counted there last June.

Mr. Brash showed off some of these nests on a sunny, but blustery day last week. ''Birds tend to be faithful to a place as long as something works,'' he said. ''If they're successful in raising young, they'll come back because success is what's it's all about.''

The five great blue herons Mr. Brash encountered on South Brother Island, he said, may be migrating birds or vagabonds from other areas along Long Island Sound. As a boat with human visitors approached, the great blue herons arched their necks and pushed off their reed-like legs, dashing off in a splendid gust of blue and gray like a band of squatters fleeing the police.

Still, Mr. Brash said, the big herons spend time on South Brother because it is safe and there are now plentiful salt marshes nearby where they can feed on small fish. And, he said, some ornithologists believe that the large herons do nest in the city, but their nests have not been spotted because herons like to build them in inaccessible places.

''We see them here during the summer, so there's reason to believe they are nesting,'' he said. ''We just haven't found their nests.''

Mr. Brash, the 45-year-old son of a Wall Street investment banker, traces his passion for birds back to his mother, a biology teacher. He trained as an ornithologist at the Yale School of Forestry and Environmental Studies.

As part of what is known as the Harbor Herons Project, parks officials and Audubon volunteers survey the 14 islands every May, when nests laden with fledgling herons and egrets can be counted, sometimes by using a long pole with a mirror at its end. Two parent herons are counted for each active nest.

Officials also post signs warning intruders that they are trespassing on a heron nesting area and risking fines. And they tinker with the vegetation. There are plans to replace inhospitable Norway maples on North Brother with gray birch, which are high enough to resist raccoons but not so high as to invite owls and hawks.

Away from the islands, parks officials, armed with grants from the United States Fish and Wildlife Service, have been working on growing grasses needed for salt marshes like those around Pelham Bay Park.

The Parks Department formed the natural resources group 20 years ago to acquire and restore parkland. It employs 30 ecologists, hydrologists, landscape architects and engineers and is working on $90 million worth of projects. Mill Rock Island in the East River and White Island in Marine Park in Brooklyn have been owned by the department since the 1950's and 1960's, respectively, but the first island picked up by the natural resources group was Prall's Island in Arthur Kill in 1984. The department now manages or monitors 10 islands, including two that are privately owned: South Brother, which is owned by Hampton Scows, a Long Island-based water freight company, and Huckleberry Island, which is owned by the New York Athletic Club and is technically in the waters off Westchester County.

The 14 islands include several improbable refuges. Mill Rock Island is just a few hundred feet from Gracie Mansion, yet about three dozen great-backed gulls and herring gulls nest near the island's perimeter, and there is evidence that a pair of black-crowned night herons may have started nesting there, according to the Audubon Society reports. U Thant Island, across from the United Nations and named for the onetime secretary general, has a dozen nests of double-crested cormorants, one of which is plainly visible to passing boats. Ruffle Bar is a 143-acre sandbar that is nearly swamped at high tide yet supports nesting gulls and oystercatchers and may soon have brush thick enough for herons.

Goose Island, acquired from the Sanitation Department within the past year, is right off the towers of Co-op City and the Metro-North railroad tracks, but 123 nests of black-crowned and yellow-crowned night herons, snowy egrets and great egrets were counted there last May. Nearby residents who spy on the island with binoculars report sightings of other unusual birds.

The 43-acre Shooters Island is between Newark Bay and the Kill Van Kull in a channel favored by cargo ships and tankers. Yet as the city began filtering its sewage in the 1970's and taking other steps to clean its waterways, wading birds began cropping up on the island.

A 1990 spill of a half-million gallons of fuel oil in the Arthur Kill waterway destroyed 700 waterfowl and damaged 200 acres of salt marsh. Adrian Benepe, the parks commissioner, said that lawsuits stemming from oil spills provided money to restore islands. The birds slowly returned to Shooters Island, and by the mid-1990's there were dozens of nests of night herons and great egrets. Now only cormorants and a single osprey pair nest there.

It is possible that the heron colonies simply moved to islands nearby, like West Siders moving to Westchester. That may be why Hoffman Island, off the eastern shore of Staten Island, has had an upsurge in its heron population. Mr. Benepe said he thought it might be necessary to acquire additional islands as alternate havens for birds.

Mr. Benepe and Mr. Brash grew up in Manhattan, and for them, managing the bird islands may be motivated as much by sentiment as by environmental concerns.

''Lots of kids in New York City are never going to go to Yellowstone,'' Mr. Brash said. ''The only wildlife they'll see are the herons.''

Photos: Ornithologists say the great blue herons that choose to settle down on islands in New York City are making a smart choice. In fact, several species are now nesting or roosting on 14 uninhabited islands in the area. (Photo by Librado Romero/The New York Times)(pg. B1); North Brother Island, once the site of a hospital, is now home to hundreds of black-crowned night heron, the city's most populous heron species. (Photo by Librado Romero/The New York Times)(pg. B8) Chart/Map: ''Island Retreats'' The bird sanctuaries on uninhabited islands are managed by New York City's Parks Department or the National Park Service with help from the Audubon Society. Map of New York City highlighting bird sanctuaries. (pg. B1)

Correction: December 5, 2003, Friday A picture caption yesterday with an article about waterfowl that thrive in New York City was published in error. The picture showed an osprey nest on Shooters Island off Staten Island, not the home of hundreds of black-crowned night herons on North Brother Island.